PROJECT SUMMARY Individual differences in the quantity and quality of parent talk and individual differences in infant visual attention predict later vocabulary development, which in turn has the cascading consequences of later cognitive development and school achievement. The proposed research studies how infants prior to their first birthday begin to learn object names, and does so in a unique approach, focusing on how visual information from the infant perspective coincide with parent naming and on how infant looking behavior selects the data to be aggregated and how that selected data changes incrementally in statistical learning. Toward this goal, we will collect a corpus of infant-perspective scenes from 8-12-month-old infants as they play with their parent in a toy room and as parents naturally name objects during play. We will analyze the referential ambiguity of the scenes that co-occur with parent naming events, by showing the scenes to infants and tracking their gaze direction in free viewing. We will use the gaze data to quantify ambiguity in terms of the uncertainty, correctness, and informativeness of the scenes as to the intended object referent. We will then construct training sets for cross-situational learning experiments from the collected scenes by manipulating the mix of high and low ambiguity trials. We will test a series of hypotheses about how infants aggregate information to learn multiple object names. Moreover, we will feed the trial-by-trial gaze data of individual infants to models to predict final learning outcomes, with the goal of specifying attentional and memory processes that support learning. Our overarching aim of the project is to show that the infant-perspective scenes co- occurring with early naming events have properties that guide and train infant visual attention and in so doing support the learning of names and their referents through the aggregation of information across multiple naming events.